I. Field
The following description relates generally to wireless communications, and more particularly to providing sequence numbering in wireless networks.
II. Background
Wireless communication systems are widely deployed to provide various types of communication content such as, for example, voice, data, and so on. Typical wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, . . . ). Examples of such multiple-access systems may include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and the like. Additionally; the systems can conform to specifications such as third generation partnership project (3GPP), 3GPP2, 3GPP long-term evolution (LTE), etc.
Generally, wireless multiple-access communication systems may simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from base stations to mobile devices, and the reverse link (or uplink) refers to the communication link from mobile devices to base stations. Further, communications between mobile devices and base stations may be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multi-output (MIMO) systems, and so forth. In addition, mobile devices can communicate with other mobile devices (and/or base stations with other base stations) in peer-to-peer wireless network configurations.
MIMO systems commonly employ multiple (NT) transmit antennas and multiple (NR) receive antennas for data transmission. The antennas can relate to both base stations and mobile devices, in one example, allowing bi-directional communication between the devices on the wireless network. Additionally, mobile devices can move throughout communications sectors served by one or more base stations, and the mobile devices can be handed off between the base stations to facilitate communicating with a desirable base station regardless of location. Radio-link layer protocol (RLP) has evolved to allow such mid-transmission handoff where a target base station can continue a transmission begun by a source sector following handoff using virtual RLP (VRLP) sequence numbers.
Using VRLP, pointers can be transmitted with handoff requests to indicate where buffered communication terminated in the source sector. The target sector, following handoff, can utilize the pointer and the remaining buffer to continue transmitting remaining data in the buffer. In this regard, over-the-air (OTA) RLP sequence numbers can be mapped to virtual sequence numbers so that the change in numbers does not completely disrupt the communication following handoff, and sectors can maintain coordinated packet sequencing.